blob: 5605a26efc57d9db3ca93471f437996dae91056e [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * fs/nfsd/nfs4idmap.c
3 *
4 * Mapping of UID/GIDs to name and vice versa.
5 *
6 * Copyright (c) 2002, 2003 The Regents of the University of
7 * Michigan. All rights reserved.
8 *
9 * Marius Aamodt Eriksen <marius@umich.edu>
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 *
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its
21 * contributors may be used to endorse or promote products derived
22 * from this software without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
25 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
26 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
27 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
31 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
32 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
33 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
34 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include <linux/config.h>
38#include <linux/module.h>
39#include <linux/init.h>
40
41#include <linux/mm.h>
42#include <linux/utsname.h>
43#include <linux/errno.h>
44#include <linux/string.h>
45#include <linux/sunrpc/clnt.h>
46#include <linux/nfs.h>
47#include <linux/nfs4.h>
48#include <linux/nfs_fs.h>
49#include <linux/nfs_page.h>
50#include <linux/smp_lock.h>
51#include <linux/sunrpc/cache.h>
52#include <linux/nfsd_idmap.h>
53#include <linux/list.h>
54#include <linux/sched.h>
55#include <linux/time.h>
56#include <linux/seq_file.h>
57#include <linux/sunrpc/svcauth.h>
58
59/*
60 * Cache entry
61 */
62
63/*
64 * XXX we know that IDMAP_NAMESZ < PAGE_SIZE, but it's ugly to rely on
65 * that.
66 */
67
68#define IDMAP_TYPE_USER 0
69#define IDMAP_TYPE_GROUP 1
70
71struct ent {
72 struct cache_head h;
73 int type; /* User / Group */
74 uid_t id;
75 char name[IDMAP_NAMESZ];
76 char authname[IDMAP_NAMESZ];
77};
78
79#define DefineSimpleCacheLookupMap(STRUCT, FUNC) \
80 DefineCacheLookup(struct STRUCT, h, FUNC##_lookup, \
81 (struct STRUCT *item, int set), /*no setup */, \
82 & FUNC##_cache, FUNC##_hash(item), FUNC##_match(item, tmp), \
83 STRUCT##_init(new, item), STRUCT##_update(tmp, item), 0)
84
85/* Common entry handling */
86
87#define ENT_HASHBITS 8
88#define ENT_HASHMAX (1 << ENT_HASHBITS)
89#define ENT_HASHMASK (ENT_HASHMAX - 1)
90
91static inline void
92ent_init(struct ent *new, struct ent *itm)
93{
94 new->id = itm->id;
95 new->type = itm->type;
96
97 strlcpy(new->name, itm->name, sizeof(new->name));
98 strlcpy(new->authname, itm->authname, sizeof(new->name));
99}
100
101static inline void
102ent_update(struct ent *new, struct ent *itm)
103{
104 ent_init(new, itm);
105}
106
NeilBrownfd39ca92005-06-23 22:04:03 -0700107static void
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108ent_put(struct cache_head *ch, struct cache_detail *cd)
109{
110 if (cache_put(ch, cd)) {
111 struct ent *map = container_of(ch, struct ent, h);
112 kfree(map);
113 }
114}
115
116/*
117 * ID -> Name cache
118 */
119
120static struct cache_head *idtoname_table[ENT_HASHMAX];
121
122static uint32_t
123idtoname_hash(struct ent *ent)
124{
125 uint32_t hash;
126
127 hash = hash_str(ent->authname, ENT_HASHBITS);
128 hash = hash_long(hash ^ ent->id, ENT_HASHBITS);
129
130 /* Flip LSB for user/group */
131 if (ent->type == IDMAP_TYPE_GROUP)
132 hash ^= 1;
133
134 return hash;
135}
136
137static void
138idtoname_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
139 int *blen)
140{
141 struct ent *ent = container_of(ch, struct ent, h);
142 char idstr[11];
143
144 qword_add(bpp, blen, ent->authname);
145 snprintf(idstr, sizeof(idstr), "%d", ent->id);
146 qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
147 qword_add(bpp, blen, idstr);
148
149 (*bpp)[-1] = '\n';
150}
151
152static inline int
153idtoname_match(struct ent *a, struct ent *b)
154{
155 return (a->id == b->id && a->type == b->type &&
156 strcmp(a->authname, b->authname) == 0);
157}
158
159static int
160idtoname_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
161{
162 struct ent *ent;
163
164 if (h == NULL) {
165 seq_puts(m, "#domain type id [name]\n");
166 return 0;
167 }
168 ent = container_of(h, struct ent, h);
169 seq_printf(m, "%s %s %d", ent->authname,
170 ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
171 ent->id);
172 if (test_bit(CACHE_VALID, &h->flags))
173 seq_printf(m, " %s", ent->name);
174 seq_printf(m, "\n");
175 return 0;
176}
177
178static void
179warn_no_idmapd(struct cache_detail *detail)
180{
181 printk("nfsd: nfsv4 idmapping failing: has idmapd %s?\n",
182 detail->last_close? "died" : "not been started");
183}
184
185
186static int idtoname_parse(struct cache_detail *, char *, int);
187static struct ent *idtoname_lookup(struct ent *, int);
188
NeilBrownfd39ca92005-06-23 22:04:03 -0700189static struct cache_detail idtoname_cache = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190 .hash_size = ENT_HASHMAX,
191 .hash_table = idtoname_table,
192 .name = "nfs4.idtoname",
193 .cache_put = ent_put,
194 .cache_request = idtoname_request,
195 .cache_parse = idtoname_parse,
196 .cache_show = idtoname_show,
197 .warn_no_listener = warn_no_idmapd,
198};
199
200int
201idtoname_parse(struct cache_detail *cd, char *buf, int buflen)
202{
203 struct ent ent, *res;
204 char *buf1, *bp;
205 int error = -EINVAL;
206
207 if (buf[buflen - 1] != '\n')
208 return (-EINVAL);
209 buf[buflen - 1]= '\0';
210
211 buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
212 if (buf1 == NULL)
213 return (-ENOMEM);
214
215 memset(&ent, 0, sizeof(ent));
216
217 /* Authentication name */
218 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
219 goto out;
220 memcpy(ent.authname, buf1, sizeof(ent.authname));
221
222 /* Type */
223 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
224 goto out;
225 ent.type = strcmp(buf1, "user") == 0 ?
226 IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
227
228 /* ID */
229 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
230 goto out;
231 ent.id = simple_strtoul(buf1, &bp, 10);
232 if (bp == buf1)
233 goto out;
234
235 /* expiry */
236 ent.h.expiry_time = get_expiry(&buf);
237 if (ent.h.expiry_time == 0)
238 goto out;
239
240 /* Name */
241 error = qword_get(&buf, buf1, PAGE_SIZE);
242 if (error == -EINVAL)
243 goto out;
244 if (error == -ENOENT)
245 set_bit(CACHE_NEGATIVE, &ent.h.flags);
246 else {
247 if (error >= IDMAP_NAMESZ) {
248 error = -EINVAL;
249 goto out;
250 }
251 memcpy(ent.name, buf1, sizeof(ent.name));
252 }
253 error = -ENOMEM;
254 if ((res = idtoname_lookup(&ent, 1)) == NULL)
255 goto out;
256
257 ent_put(&res->h, &idtoname_cache);
258
259 error = 0;
260out:
261 kfree(buf1);
262
263 return error;
264}
265
266static DefineSimpleCacheLookupMap(ent, idtoname);
267
268/*
269 * Name -> ID cache
270 */
271
272static struct cache_head *nametoid_table[ENT_HASHMAX];
273
274static inline int
275nametoid_hash(struct ent *ent)
276{
277 return hash_str(ent->name, ENT_HASHBITS);
278}
279
NeilBrownfd39ca92005-06-23 22:04:03 -0700280static void
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281nametoid_request(struct cache_detail *cd, struct cache_head *ch, char **bpp,
282 int *blen)
283{
284 struct ent *ent = container_of(ch, struct ent, h);
285
286 qword_add(bpp, blen, ent->authname);
287 qword_add(bpp, blen, ent->type == IDMAP_TYPE_GROUP ? "group" : "user");
288 qword_add(bpp, blen, ent->name);
289
290 (*bpp)[-1] = '\n';
291}
292
293static inline int
294nametoid_match(struct ent *a, struct ent *b)
295{
296 return (a->type == b->type && strcmp(a->name, b->name) == 0 &&
297 strcmp(a->authname, b->authname) == 0);
298}
299
300static int
301nametoid_show(struct seq_file *m, struct cache_detail *cd, struct cache_head *h)
302{
303 struct ent *ent;
304
305 if (h == NULL) {
306 seq_puts(m, "#domain type name [id]\n");
307 return 0;
308 }
309 ent = container_of(h, struct ent, h);
310 seq_printf(m, "%s %s %s", ent->authname,
311 ent->type == IDMAP_TYPE_GROUP ? "group" : "user",
312 ent->name);
313 if (test_bit(CACHE_VALID, &h->flags))
314 seq_printf(m, " %d", ent->id);
315 seq_printf(m, "\n");
316 return 0;
317}
318
319static struct ent *nametoid_lookup(struct ent *, int);
NeilBrownfd39ca92005-06-23 22:04:03 -0700320static int nametoid_parse(struct cache_detail *, char *, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321
NeilBrownfd39ca92005-06-23 22:04:03 -0700322static struct cache_detail nametoid_cache = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323 .hash_size = ENT_HASHMAX,
324 .hash_table = nametoid_table,
325 .name = "nfs4.nametoid",
326 .cache_put = ent_put,
327 .cache_request = nametoid_request,
328 .cache_parse = nametoid_parse,
329 .cache_show = nametoid_show,
330 .warn_no_listener = warn_no_idmapd,
331};
332
NeilBrownfd39ca92005-06-23 22:04:03 -0700333static int
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334nametoid_parse(struct cache_detail *cd, char *buf, int buflen)
335{
336 struct ent ent, *res;
337 char *buf1;
338 int error = -EINVAL;
339
340 if (buf[buflen - 1] != '\n')
341 return (-EINVAL);
342 buf[buflen - 1]= '\0';
343
344 buf1 = kmalloc(PAGE_SIZE, GFP_KERNEL);
345 if (buf1 == NULL)
346 return (-ENOMEM);
347
348 memset(&ent, 0, sizeof(ent));
349
350 /* Authentication name */
351 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
352 goto out;
353 memcpy(ent.authname, buf1, sizeof(ent.authname));
354
355 /* Type */
356 if (qword_get(&buf, buf1, PAGE_SIZE) <= 0)
357 goto out;
358 ent.type = strcmp(buf1, "user") == 0 ?
359 IDMAP_TYPE_USER : IDMAP_TYPE_GROUP;
360
361 /* Name */
362 error = qword_get(&buf, buf1, PAGE_SIZE);
363 if (error <= 0 || error >= IDMAP_NAMESZ)
364 goto out;
365 memcpy(ent.name, buf1, sizeof(ent.name));
366
367 /* expiry */
368 ent.h.expiry_time = get_expiry(&buf);
369 if (ent.h.expiry_time == 0)
370 goto out;
371
372 /* ID */
373 error = get_int(&buf, &ent.id);
374 if (error == -EINVAL)
375 goto out;
376 if (error == -ENOENT)
377 set_bit(CACHE_NEGATIVE, &ent.h.flags);
378
379 error = -ENOMEM;
380 if ((res = nametoid_lookup(&ent, 1)) == NULL)
381 goto out;
382
383 ent_put(&res->h, &nametoid_cache);
384 error = 0;
385out:
386 kfree(buf1);
387
388 return (error);
389}
390
391static DefineSimpleCacheLookupMap(ent, nametoid);
392
393/*
394 * Exported API
395 */
396
397void
398nfsd_idmap_init(void)
399{
400 cache_register(&idtoname_cache);
401 cache_register(&nametoid_cache);
402}
403
404void
405nfsd_idmap_shutdown(void)
406{
407 cache_unregister(&idtoname_cache);
408 cache_unregister(&nametoid_cache);
409}
410
411/*
412 * Deferred request handling
413 */
414
415struct idmap_defer_req {
416 struct cache_req req;
417 struct cache_deferred_req deferred_req;
418 wait_queue_head_t waitq;
419 atomic_t count;
420};
421
422static inline void
423put_mdr(struct idmap_defer_req *mdr)
424{
425 if (atomic_dec_and_test(&mdr->count))
426 kfree(mdr);
427}
428
429static inline void
430get_mdr(struct idmap_defer_req *mdr)
431{
432 atomic_inc(&mdr->count);
433}
434
435static void
436idmap_revisit(struct cache_deferred_req *dreq, int toomany)
437{
438 struct idmap_defer_req *mdr =
439 container_of(dreq, struct idmap_defer_req, deferred_req);
440
441 wake_up(&mdr->waitq);
442 put_mdr(mdr);
443}
444
445static struct cache_deferred_req *
446idmap_defer(struct cache_req *req)
447{
448 struct idmap_defer_req *mdr =
449 container_of(req, struct idmap_defer_req, req);
450
451 mdr->deferred_req.revisit = idmap_revisit;
452 get_mdr(mdr);
453 return (&mdr->deferred_req);
454}
455
456static inline int
457do_idmap_lookup(struct ent *(*lookup_fn)(struct ent *, int), struct ent *key,
458 struct cache_detail *detail, struct ent **item,
459 struct idmap_defer_req *mdr)
460{
461 *item = lookup_fn(key, 0);
462 if (!*item)
463 return -ENOMEM;
464 return cache_check(detail, &(*item)->h, &mdr->req);
465}
466
467static inline int
468do_idmap_lookup_nowait(struct ent *(*lookup_fn)(struct ent *, int),
469 struct ent *key, struct cache_detail *detail,
470 struct ent **item)
471{
472 int ret = -ENOMEM;
473
474 *item = lookup_fn(key, 0);
475 if (!*item)
476 goto out_err;
477 ret = -ETIMEDOUT;
478 if (!test_bit(CACHE_VALID, &(*item)->h.flags)
479 || (*item)->h.expiry_time < get_seconds()
480 || detail->flush_time > (*item)->h.last_refresh)
481 goto out_put;
482 ret = -ENOENT;
483 if (test_bit(CACHE_NEGATIVE, &(*item)->h.flags))
484 goto out_put;
485 return 0;
486out_put:
487 ent_put(&(*item)->h, detail);
488out_err:
489 *item = NULL;
490 return ret;
491}
492
493static int
494idmap_lookup(struct svc_rqst *rqstp,
495 struct ent *(*lookup_fn)(struct ent *, int), struct ent *key,
496 struct cache_detail *detail, struct ent **item)
497{
498 struct idmap_defer_req *mdr;
499 int ret;
500
501 mdr = kmalloc(sizeof(*mdr), GFP_KERNEL);
502 if (!mdr)
503 return -ENOMEM;
504 memset(mdr, 0, sizeof(*mdr));
505 atomic_set(&mdr->count, 1);
506 init_waitqueue_head(&mdr->waitq);
507 mdr->req.defer = idmap_defer;
508 ret = do_idmap_lookup(lookup_fn, key, detail, item, mdr);
509 if (ret == -EAGAIN) {
510 wait_event_interruptible_timeout(mdr->waitq,
511 test_bit(CACHE_VALID, &(*item)->h.flags), 1 * HZ);
512 ret = do_idmap_lookup_nowait(lookup_fn, key, detail, item);
513 }
514 put_mdr(mdr);
515 return ret;
516}
517
518static int
519idmap_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen,
520 uid_t *id)
521{
522 struct ent *item, key = {
523 .type = type,
524 };
525 int ret;
526
527 if (namelen + 1 > sizeof(key.name))
528 return -EINVAL;
529 memcpy(key.name, name, namelen);
530 key.name[namelen] = '\0';
531 strlcpy(key.authname, rqstp->rq_client->name, sizeof(key.authname));
532 ret = idmap_lookup(rqstp, nametoid_lookup, &key, &nametoid_cache, &item);
533 if (ret == -ENOENT)
534 ret = -ESRCH; /* nfserr_badname */
535 if (ret)
536 return ret;
537 *id = item->id;
538 ent_put(&item->h, &nametoid_cache);
539 return 0;
540}
541
542static int
543idmap_id_to_name(struct svc_rqst *rqstp, int type, uid_t id, char *name)
544{
545 struct ent *item, key = {
546 .id = id,
547 .type = type,
548 };
549 int ret;
550
551 strlcpy(key.authname, rqstp->rq_client->name, sizeof(key.authname));
552 ret = idmap_lookup(rqstp, idtoname_lookup, &key, &idtoname_cache, &item);
553 if (ret == -ENOENT)
554 return sprintf(name, "%u", id);
555 if (ret)
556 return ret;
557 ret = strlen(item->name);
558 BUG_ON(ret > IDMAP_NAMESZ);
559 memcpy(name, item->name, ret);
560 ent_put(&item->h, &idtoname_cache);
561 return ret;
562}
563
564int
565nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen,
566 __u32 *id)
567{
568 return idmap_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, id);
569}
570
571int
572nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen,
573 __u32 *id)
574{
575 return idmap_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, id);
576}
577
578int
579nfsd_map_uid_to_name(struct svc_rqst *rqstp, __u32 id, char *name)
580{
581 return idmap_id_to_name(rqstp, IDMAP_TYPE_USER, id, name);
582}
583
584int
585nfsd_map_gid_to_name(struct svc_rqst *rqstp, __u32 id, char *name)
586{
587 return idmap_id_to_name(rqstp, IDMAP_TYPE_GROUP, id, name);
588}